6 th ICPT, Sapporo, Japan, July 2008 A UNIFIED OPTIMIZATION PROCEDURE FOR ROAD ASSET MANAGEMENT Koji Tsunokawa Professor, Department of Environmental Science and Infrastructure Engineering, Graduate School of Science and Engineering, Saitama University Email: kojit@mail.saitama-u.ac.jp Dinh Van Hiep Graduate student, Department of Environmental Science and Infrastructure Engineering, Graduate School of Science and Engineering, Saitama University Email: dinhhiepvan@yahoo.com ABSTRACT This paper presents a unified and coherent procedure for optimizing the allocation of a system-wide budget over its constituent subsystems, be it infrastructure components or sub-networks. We will use the net present value (NPV) as the common denominator for measuring the desirability of management programs for all asset subsystems. Using an asset subsystem optimizer (ASSO) the NPVs are first predicted for several budget levels to construct the NPV function of each asset subsystem. For a given system-wide budget, the NPV functions of all subsystems are then used to find the optimal allocation among all subsystems. Once optimal budget allocation has been found, optimal management strategy for each subsystem can be found by running the ASSO with the optimally allocated budget. The applicability and accuracy of the proposed procedure is demonstrated using a case study. KEY WORDS Road Asset Management; Budget Allocation; Subsystem; Capital Budgeting Problem; Decomposition Algorithm.